Compounds of nicotine



Patented Aug. 22, 19 44 QFFJ B comounns ormc'o'rmn" Claude R. Smith, Philadelphia, Pa, minor to 7 Claude R. Wickard, as Secretary of Agriculture of the United States cessors in ofllce No Drawing.

otAmerica, and his suc- Application September. 2o, i941, Serial No. 411,702 I i "sclaimswcizsc -z'm). (Granted under" the act or March a, 1883, as p Thi application is made March'3, 1883, as amended by the act of April 30, 1928, and theinventiori herein described and claimed, it patented, may be manufactured and used by or for the Government of the United States of America for governmental purpose J without the payment to me of any royalty thereon.

The primary objective of this in-ventionis the production-of new compounds of. mcotine which offer resistance to the often undesirable eflects of moisture, ,dew, rain, sun, etc., and can be used efiectively against injurious insects upon vegetation.

Many of these new compounds exert a fumigating etfect while in the 'dry dust form superior to any p eviously known or used up to'this time. This fumigating effect results from the combinations-of nicotine with such volatile acids as benzoic, salicylic, etc. In addition to the advantages just enumerated, the'comp'ounds containing zinc or copper, both of which are components of fungicidesmay supply the necessary fungicidal properties in addition totheir insecticidal action. The designation fixed nicotine compound has been customarily applied to such weather-resistfng materialsasthe tannate, humate, bensent more convenient physical forms and manyof them possess excellent keeping properties. The natural color of many of the salts afiord an additional safety factor against mistaken identification.

Important difierences are'to be expected in the mode of action of my compounds and nicotine bentonite considered hitherto as the most metal.

amended April 30,1928; 370 0. G. 757):

under the act of' provides nicotine and, metal forfungicidal and insecticidal action.

jMy compounds may be described as .coordlnated or double salts with the metal probably exerting an auxiliary valency toward the nicotine molecule. The nature of the acid isan essential requirement. Most ordinary acids such as boric, oxalic, phosphoric, etc., either do not serve for double ,salt formation orno relatively insoluble combinations exist.

metals iron, zinc, copper, nickel, cobalt and cadmium; They are further limited in the nature of the acid used to bind the nicotine and the The acid is selected from a group of acids consisting of hydrocyanic, thiocyanic, hy-

. ring including benzoic, o-benzoic, o-benzoyl benpromising of the fixed nicotine products. Bentonite releases nicotine only by the hydrolysis and volatilization of the free nicotine and when the ratio of bentonite to nicotine increases this action is much reduced. On dry days even when hot, verylittle nicotine will be released. With a number of my new compounds, such as the benzoates and salicylates, the fumigating effect is increased by heat and dryness with simultaneous release of nicotine and the volatile acid. Under moist conditions, a small but definite solubility droferrocyanic, hydroferricyanic, chromic, benzoic, salicylic, o-benzoyl benzoic and picric acids.

The acids containing the C=N group are highly susceptible to polymerization and with the metals iron, zinc, copper, nickel, cobalt andv and alkaline earth metals.

The acids containing the unsaturated benzene zoic, picric and salicylic acids are also highly effective in double salt formation producing compounds which are generally crystalline and often quite insoluble in water. The cadmium nicotine benzoate, however, is rather soluble and separates only in concentrated solutions. The double chromates are'generally fairly soluble and must be prepared from concentrated solutions. The zinc double 'salt, however, is, very insoluble but maybe secured in a finely divided crystalline form. The polymerizing tendency of the chro- -mates is seen in the existence of many poly plication. It will require further study to establish which groups and their positions in the benzene acids which either do or do not function for acceptable double salt formation. These metals,

' employed in my invention, are known as of the viously stated auxiliary valencies in their complexion forming compounds.

some similar compounds have been described containing ammonia, pyridine, ethylene dicmine, etc., but none containing nicotine. Most of my compounds even have no corresponding analogs in any other organic base complex salts now described in the art. Inthe following description when a metalsalt or metal is referred to it is understood to mean one of the metals designated above.

It is quite probable that other metals such as titanium, platinum, gold, etc., would serve to produce many if not all of the corresponding nicotine complex salts but their cost would defeat the primary purpose of this invention. The process involved in the preparation of my new compounds is closely related to their usual composition as represented by the formula mm (CwHmNam) air and can be prepared only by the exclusion of oxygen such as the double nicotine ferrous ferrocyanide. The ferrous nicotine double thiocyanate, however, is a crystalline compound easily prepared before appreciable oxidation results.

With polyvalent acids such as hydroferrocyanic with a valency of d, n is d, and the formula for a bivalent metal would be For purpose of preparation one half of the acid is always used to form the metallic salt and the other half to form the equivalent nicotine salt. The applicant does not claim that the percentage of nicotine will always correspond to the general formula mnJKCwHHNLHX) although approximated closely with the bennoates, picrates and salicylates. The highly complex nature of the double cyanides, ferrocyanides, ferricyanides prevents an exact formulation of the resulting compound but should not obviate their usefulness under controlled conditions.

In the preparing of new compounds it should be understood that the pI-I range of the individual solutions and the final resulting mixture containing the precipitated double salt should be adjusted to keep within the range of pH 5-7.5. If the normal salt is desired in the greatest yield it is best to have all solutions slightly acid around pH 5 and make the final adjustment to pH 7-7.5 to complete the precipitation. Excessive acidity will tend to dissolve and disrupt the compounds while excessive alkalinity will form admixed basic salts with a lowered content of nicotine. The resulting compounds of this invention represent essentially combinations of neutral salts. The ferrocyanide compounds are very insoluble, and colloidal in nature causing dimculty in filtration. They may be found particularly adaptable to spray mixtures.

In order to spread the action of the dry powders it may be desirable to dilute them with such materials as talc, starch, kaolin and other neutral products commonly used as diluents for insecticides.

In the preparation of the copper, nickel and cobalt compounds I prefer to avoid the presence 15 two general processes employed in the preparation of my compounds both of which are based onthe formula MxmmcmHuNm-m). Process No. 1, to be described below, can be employed with many but not all of them. It can be em ploycd when the metallic salt can be first readily prepared and then brought into contact with the equivalent nicotine salt. For example copper benzoate can be first prepared and washed free of soluble salts and brought into contact with the nicotine benzoate dissolved in water. Copper salicylate, however, is very soluble and process No. 2 should be employed. These two processei are as follows:

Process No. 1: In water solution one molecule of the metallic salt of the metal combined with the acid selected is treated with the equivalent amount of the nicotine salt of the acid. After varying intervals of time the maximum of the nicotine salt is removed from the solution. The freshly prepared metallic salt while still wet reacts more rapidly than after drying. If the nicotine salt of the acid is not available, use equivalent proportions of a soluble salt of nicotine with a soluble salt of the acid where the metal may be sodium, potassium, ammonium, calcium, magnesium or other non-coordinating metal.

Process No. 2: Is generally applicable toall compounds and consists in bringing together a soluble salt of the metal with the equivalent quantity of a soluble salt of the acid such as the sodium, potassium, ammonium, calcium, magnesium or other non-coordinating metal salt and the equivalent quantity of the nicotine salt of the acid. If the nicotine salt is not available it is only necessary to use an equivalent amount of some nicotine salt with an equivalent of the soluble salt of the acid such as the sodium, potassium, ammonium, calcium, magnesium or other non-coordinating metal. The double salt obtained will contain only the acid selected from the group of polymerizing acids of this invention and, if desired, may be washed free of contaminating soluble salts. The following examples will serve to fully enable any one with a knowledge of chemistry to prepare the new compounds claimed in the invention.

Examples 1. One mol of copper acetate is added to a mixture of 2 mols of sodium benzoate and 2 mols of nicotine benzoate all in water solution. If normal solutions of these three compounds are used the precipitated copper nicotine compound forms a rather dense mixture so I prefer dilution with more water before filtration is made. A slight excess of dissolved benzolc acid will produce a mixture with a pH between 5-7. This pH may be adjusted to 7-7.5 with dilute nicotine alkaloid solution in water to secure maximum precipltation yet avoid the production of basic salts. The

washed and dried copper nicotine benzoate analyzes 7.7% for copper and 37 to 38% for nicoglqne: theory for Cu is 7.27% and for nicotine -36.6% nicotine; theory 3 7.1.

""assa-iss Y y 2; 11ml of imcsemte is added to'a'mixtiirs oi-2mols oi sodium benzoate and2 mols of nicotine benz'oate all in water solution preierably working on the acid side with excess of soluble benzoic acid. It normal solutions are to be'mixed considerable dilution maybe employed for the 1 product. Theory for nicotine 37%; found 38%.

is abluishredtoredinoolor but am. brownish on prolonged washing probably due to hydrolysis. j

'16. Use one mol otierrous ammoniumsulphate dissolved in'water and add to a mixtureoi' 4 'mols oi sodium thiocyanateand 2-mols oi nico-:

tine monohydrochloride. The precipitated double salt is abrownish white crystalline product.

3. One mol of copper acetate is added to 2 mols of sodium salicylate without the formation a precipitate when working with their normal soiutions in water. This mixture may be poured,

slowly into water containing 2 mols oi nicotine sa'licylate forming a greenish to lavender colored precipitate of copper nicotine salicylate. More acid compounds are green while the neutral or slightly alkaline are lavender in color. Analysis for nicotine 33%; theory 34%. I

4. One moi of copper sulphate is added to 2 mols oi sodium-benzoate all inwater solution.

Filter, wash and suspend the wet crystals in 2 mols of nicotine b'enzoate in water solution, agitating occasionally during a period of several hours. The filtered and dried product contained- 5. One mol of copper sulphate is added to a mixture of 2 mols of sodium thiocyanate and 2 mols of an equivalent nicotine thiocyanate produced by a mixture of 2 mols of nicotine hydrochloride and 2 mols of sodiumthiocyanate. Cupric nicotine thiocyanate is produced a's a bright l7-.:One mol of ferric chloride is added to a mixture of 6 mols oi sodium benzoate and 3 mols of nicotine monohydrochloride. The double salt is a very insoluble bull. colored product.

, 18. One moi of ferric chloride is added to sodium salicylate and nicotine salicylate Just as in Example '17. 1 The purplish red double salt is precipitated and can be readily filtered.

19. To a mixture of two mols oipotassium ierrocyanlde and .4 mols of nicotine hydrochloride a solution of ionic ammonium sulphate containchrom ate and one mol of nicotine alkaloid a green colored product quite insoluble in water.

On boiling with alkaiie's cupric oxide-is formed.

6. Copper acetate in aqueous'solution is added to a mixture of two mols or sodium cyanide and 1 mol of .a neutral nicotine salt until a slight excess of copper is presente salt to be expected corresponding to the formula expected Cu(CN) 2.2Cl0Hl4N2-HCN loses cyanogen 'anda brown insoluble salt analyz ing as nicotine vcuprous cyanide "is produced.

-7. Two molsoi copper acetate is added to a mixture of 2 mols oi-a ierrooyanide salt and! mols of nicotine hydrochloride. The double fer rocyanide has a bluish red color, illters well, although the gelatinous product driesslowly;

8. Two mols of zinc acetate is used instead of the copper acetate in Example 'I. The product.

is yellowish white,,highly colloidal and filters slowly.

9. One mol of copper acetate is added to a mix- 11. Instead of copper acetate in Example 9 use I nickel acetate to form a greenish yellow double picrate which seems to suffer decomposition on standing in the dry state.

12. Instead of copper acetate in Example 5 use nickel acetate and obtain a crystalline blue double thiocyanate. l

13. Instead of copper acetate in Example 5 use cobalt acetate and obtain a crystalline pink double salt.

l4. Instead of copper acetate in Example 5 use cadmium acetate and obtain a crystalline white double salt.

15. Use one mol of ferric chloride and a mixture of 6mols of sodium thiocyanate and 3 mols colloidal yellow zinc nicotine double salt ih obtained. a

22. If one moi of copper acetate is added to 1' mol of potassium dichromate andl mol of nicotine alkaloid a yellow double salt oi copper nicotine-chromate is obtained. The solutionsshould be fairly concentrated as the product is fairly soluble in water.

23.1! one mol oi-zinc acetate is added to a mixture containing 2 mols of sodium o-benzoyl benzoate and 2 mols oi nicotine o-benzoyl benzoate a white crystalline double salt is formed.

24.11 one mol of copper acetate is added to a mixture containing 2 mols of sodium o-benzoyi benzoate and 2 mols of nicotine o-benzoyl' benzoate a light blue doublesalt is formed. The

product is quite insoluble and forms a powder of low specific gravity.

25..As in Example3 use cadmium acetate and obtain a white insoluble crystalline double salt I tine saiicylate.

salt of zinc.nicotine cyanide.

27. Using 1 mol of zinc chloride and 4 mols of potassium cyanide and 2. mols of nicotine hydrochloride I obtain a white crystalline double The use of some ammonium chloride seems to help the product iorm flne crystals which are easier to filter.

of nicotine monohydrochloride. The double salt I 28. Ii. zinc acetate is used as in Example 3 a white, highly insoluble, crystalline zinc nicotine tice it is advisable to use the sulphates oi the metals and calcium salts of the acids whenever possible, since the resulting calcium sulphate (CaS042I-IzO) is nonhygroscopic and need'not be washed out of the material when the resulting nicotine double salt is to be employed as an insecticide in dust form. In'some cases it will be necessary to restrict the chemicals employed to'those-available on the market.

Having thus described my invention, what I clsim i'or Letters Patent is:

i. A double salt of nicotine and a metal, said salt comprising copper nicotine benzoste.

2. A double salt of nicotine and a. metal, said salt comprising zinc nicotine benzoate.

3. A double salt of nicotone and a metal, said salt comprising ferric nicotine benzoate.

4. A double salt oi nicotine and a. metal chosen from the group consisting of iron, zinc, copper, nickel, cobalt, and cadmium having an acid radical selected from the group oi acids conwhere M is 1 meta! chosen from the group consisting oi iron, anc, copper, nickel, cobalt and cadmium; n is an integer corresponding to the valency of M; and X is an acid radical selected from the group of acids coneietin: oi picric,

benzoic, salicylic, end o-benmyi bensoic.

CLAUDE B. SMITH. 

